Hadith on Wudu: Light sleep does not invalidate ablution

Anas ibn Malik reported: The companions of the Messenger of Allah, peace and blessings be upon him, would sleep (lightly) and then perform prayer without renewing ablution.

Source: Ṣaḥīḥ Muslim 376

Grade: Sahih (authentic) according to Muslim

At-Tirmidhi said, “The scholars disagreed regarding ablution for one who slept. The majority of them are of the opinion that it is not an obligation to perform ablution if one slept sitting or standing, unless one slept while lying down.”